Efforts to improve the state of the art in the area of solar power generation; particularly in the area of building mounted generation (also known as “Building Integrated Photovoltaics” or BIPV) has been receiving ever increasing industry focus over the last few years. BIPV products are exposed to significant variations in environmental loadings. They are preferably located in direct sunlight where they are subject to additional temperature loadings (beyond daily and seasonal ambient swings) due to radiant cooling and heating. It is possible for the devices to see 60 to 80° C. daily changes in more severe environments. The BIPV system design needs to address the impacts of these environmental conditions including ensuring good electrical contacts within and among components of the system.
Therefore, various testing protocols (e.g. UL 1703) are used to determine the product's capability to handle these temperature variations, for example as illustrated in FIG. 10. One test of particular interest performed on the product is a Wet Insulation Resistance test (“Wet Hi-pot”), found in UL 1703, section 27. For example, the PV device should not exhibit a dielectric breakdown as a result of an applied direct current voltage (e.g. about 500 volts) while immersed in a non-corrosive liquid. Moreover, there is a desire to ensure good electrical contact at the time of installation that will minimize electrical contact failures during usage. These tests may be required to be performed before and/or after thermal cycling of the device(s).
These protocols may also apply to a full photovoltaic system where two or more photovoltaic devices are connected together. Parts are subject to stresses and displacements relative to each other as they expand and contract with temperature changes. Similarly, the surface the photovoltaic devices are mounted to may change as a function of temperature, humidity, or as the structure settles with time. In cases where the connections are not connected with wires or flexible members there is likelihood of leakage paths at these device to device connections if not properly designed or installed. The issue of leakage paths is contemplated in both the connection of multiple devices and within a single device.
The present invention is directed to at least one unique solution to the problems discussed above.
Among the literature that may pertain to this technology include the following patent documents: U.S. Pat. No. 7,708,593; U.S. Pat. No. 7,655,508; U.S. Pat. No. 7,654,843; U.S. Pat. No. 6,948,976; U.S. Pat. No. 6,955,558; PCT/US20091042496; U.S. Pub. 20080101002; U.S. Pub. 2004711107A; U.S. Pat. No. 7,012,188; and U.S. Pat. No. 7,592,537 all incorporated herein by reference for all purposes.